Selected Behaviors That Increase Risk for HIV Infection,
Other Sexually Transmitted Diseases, and Unintended Pregnancy
Among High School Students -- United States, 1991

Since the 1970s, sexual activity has increased among
adolescents in the United States (1); at the same time, rates of
sexually transmitted diseases (STDs) (1), unintended pregnancy (2),
and -- beginning in the 1980s -- human immunodeficiency virus (HIV)
infection (3,4) also have increased among adolescents. This report
presents 1991 self-reported data from students in grades 9-12 about
behaviors that can result in HIV infection, other STDs, or
unintended pregnancy.

Data were collected from two school-based components of CDC's
Youth Risk Behavior Surveillance System (5): 1) state and local
Youth Risk Behavior Surveys (YRBSs) conducted by departments of
education in 23 states * and 10 cities during April-May 1991 and 2)
the national YRBS conducted during the same period. The 33 state
and local sites drew probability samples from well-defined sampling
frames of schools and students in grades 9-12. Seventeen sites had
adequate school- and student-response rates to allow computation of
weighted results of known precision; 16 sites had overall response
rates below 60% or unavailable documentation, which precluded
making estimates of known precision. The national survey used a
three-stage sample design to obtain a sample of 12,272 students
representative of students in grades 9-12 in the 50 states and the
District of Columbia.

For the state and local surveys, school-response rates ranged
from 48% to 100%; student-response rates ranged from 44% to 96%
(6); and state and local sample sizes ranged from 369 to 5834
students. The grades and sex of students were distributed evenly
for most samples, but the racial/ethnic characteristics of the
samples varied. For the national survey, the school-response rate
was 75% and the student-response rate was 90%. Risk behaviors
addressed in the survey included having sexual intercourse, having
sexual intercourse with multiple sex partners, injecting-drug use
(IDU) **, not practicing contraception, and not using condoms.

Of students participating in the state and local surveys, 33%-
79% (median: 55%; national prevalence: 54%) reported ever having
had sexual intercourse (Table 1); 54%-78% (median: 70%; national
prevalence: 69%) reported being currently sexually active (i.e.,
having had sexual intercourse during the 3 months preceding the
survey); and 8%-46% (median: 20%; national prevalence: 19%)
reported having had sexual intercourse with four or more partners
during their lifetime. In 27 of 28 sites, male students were more
likely than female students to report ever having had sexual
intercourse and having had four or more sex partners during their
lifetime while, in 26 of 28 sites, female students were more likely
than male students to report being currently sexually active.

Among the state and local surveys, the percentage of students
who reported IDU ranged from 1% to 4% (median: 2%; national
prevalence: 2%) (Table 1). In all sites, 5% or less of male and
female students reported IDU.

Among students participating in the state and local surveys
who reported current sexual activity, 58%-87% (median: 77%;
national prevalence: 82%) reported they or their partner used
contraception*** at last sexual intercourse and 28%-53% (median:
48%; national prevalence: 46%) reported they or their partner had
used a condom at last sexual intercourse (Table 2). In all sites,
male and female students reported similar rates of contraceptive
use.

Editorial Note

Editorial Note: The findings in this report and in previous studies
(7,8) indicate that a substantial proportion of students throughout
the United States engage in behaviors that simultaneously place
them at risk for HIV infection, other STDs, and unintended
pregnancy. The only completely effective means of preventing
unintended pregnancy and STDs is to refrain from sexual
intercourse. For persons who are sexually active, the risk for
unintended pregnancy can be decreased by the correct and consistent
use of condoms or other contraceptives. The risk for STDs,
including HIV, can be decreased by correctly and consistently using
condoms, maintaining a monogamous sexual relationship with an
uninfected partner, reducing the number of sex partners, and
avoiding IDU.

The findings in this report can be used to plan and evaluate
national, state, and local progress toward achieving national
health objectives for the year 2000. Objectives 5.4, 18.3, and 19.9
are to reduce the proportion of adolescents who have engaged in
sexual intercourse to 15% or less by age 15 years and to 40% or
less by age 17 years (9). Only two sites have met the 40% objective
for students in grades 9-12. Objective 5.5 is to increase the
proportion of adolescents aged less than or equal to 17 years who
have had sexual intercourse but have abstained from such activity
for the previous 3 months to at least 40%; only two sites have met
this objective. Objective 5.6 is to increase the proportion of
sexually active, unmarried persons aged less than or equal to 19
years who use contraception to at least 90%; no site met this
objective. Objectives 18.4 and 19.10 are to increase the use of
condoms during last sexual intercourse among sexually active,
unmarried females and males aged 15-19 years to 60% and 75%,
respectively; no site met these objectives.

Nationwide, HIV education is required by 78% of districts for
students in grades 6-8 and 47% of districts for students in grades
9-12 (10). Special efforts must be directed toward providing
programs for students in grades 9-12 who are at greatest risk for
HIV infection. CDC has been providing fiscal and technical
assistance to all state education agencies, 16 local education
agencies in cities with the highest number of AIDS cases, and 23
national organizations to make available effective HIV education
programs for youth. These programs are intended to help adolescents
develop skills they will need to remain sexually abstinent and to
increase the use of contraceptives, including condoms, among youth
who do not refrain from having sexual intercourse.

Holtzman D, Greene BZ, Ingraham GC, Daily LA, Demchuk DG, Kolbe
LJ. HIV education and health education in the United States: a
national survey of local school district policies and practices. J
Sch Health 1992;62:421-7.

The District of Columbia, Puerto Rico, and the Virgin Islands are
categorized as states for funding purposes.
** Students were classified as injecting-drug users only if they 1)
reported such behavior that was not prescribed by a physician and
2) answered affirmatively to any of these questions: "During your
life, how many times have you used any form of cocaine including
powder, crack, or freebase?"; "During your life, how many times
have you used any other type of illegal drug such as LSD, PCP,
ecstacy, mushrooms, speed, ice, heroin, or pills without a doctor's
prescription?"; or "During your life, how many times have you taken
steroid pills or shots without a doctor's prescription?"
*** Contraceptive methods included birth control pills, condoms,
withdrawal, or some other reported method.

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